1. Field of the Invention
The present invention relates to a data transmission method, and more particularly, a wireless data transmission method for mobile devices.
2. Description of the Prior Art
As the popularity of mobile devices increases and the demand for higher quality increases, focus is being placed on the development of next generation mobile network technology. The evolution of wireless communication includes the earlier first generation analog communications technology (1G), the second generation Global System for Mobile (GSM) communications technology (2G), the third generation Wideband Code Division Multiple Access (WCDMA) communications technology (3G), up to the latest fourth generation Long-Term Evolution (LTE) communications technology (4G). Each generation of the communications technologies is established using different algorithms. Aside from transmission rate, against channel fading, spectrum density, and power consumption, the signal penetration distance is also considered. The transmission signal of the third generation and fourth generation communications technology uses orthogonal frequency division multiplexing modulation to increase the transmission strength and the penetration distance.
However, as the popularity of smart phones and wireless mobile devices grow, intercommunication of multimedia files and application programs may be implemented by using wireless network. The abovementioned multimedia files and application programs can be files having a size as big as gigabytes (GB). Therefore, even though fourth generation communications technology is used for transmission, insufficient transmission rate could still be an open question. At present, researches are being done to develop a fifth generation communications technology and the fifth generation communications technology is predicted to be available by year 2020. The fifth generation communications technology is predicted to transmit 1 GB data per minute by using radio frequency of 28 GHz with maximum distance of 2 kilometers. Although the fifth generation communications technology is expected in the future to increase the transmission speed, it is important to develop a transmission method for increasing the transmission rate without dramatically modifying the hardware of the mobile devices.
For the presently available smart phones and wireless mobile devices, most of the devices are able to link to the internet by using at least one communication interface. The at least one communication interface can be the interface of wireless wide area network (WWAN) of 2G, 3G and 4G, wireless local area network (WLAN), or Bluetooth. However, a mobile device can only use one communication interface with respect to a specific communication technique. In other words, utilization of two or more communication interfaces (or say, two or more communication techniques) at the same instant is not available.
Therefore, it is important to develop a method for increasing the transmission rate in conjunction with optimizing the bandwidth allocation of the mobile devices by using several heterogeneous networks without greatly modifying hardware of the mobile devices.